Switch mechanism



July 15, 1958 B. A. KNAUTH 2,843,698

SWITCH MECHANISM Filed 001:. 11, 1955 35 12 I9 37 \L 37 ,v i 19 INVENTOR. BER 7/1040 .4. KA/AW'I/ BMW/@5077 United States Patent Ofiice 2,843,698 Patented July 15, 1958 SWITCH MECHANISM Berthold A. Knauth, High Falls, N. Y.

Application October 11, 1955, Serial No. 539,827

6 Claims. (Cl. 200-87) This invention relates to switch mechanisms.

It is an object of the present invention to provide an improved switch mechanism which is simple, yet sturdy and durable of construction, and which will operate consistently over a relatively long period of time without repair.

it is another object of the present invention to provide a switch mechanism of the above type wherein the tendency to intermittent circuit interruption owing to vibration is minimized and which embodies a novel snap action which is extremely valuable from an electro-mechanical viewpoint and wherein the life of the contacts is appreciably extended.

It is still another object of the present invention to provide a switch mechainsrn of the above type which may be used in connection with flow meters where it is capable of being actuated mechanically and wherein the switch mechanism will function even when submerged in the cavity of the flow meter through which gasoline or other liquid-is passing although the switch mechanism itself is not limited to this application and can, in fact, be adapted for use wherever manual operation is required, for example, in switches for walls, or the like.

Further objects of the invention are to provide a switch in Which there is only one moving part, namely, the loose magnet; in which the region of the are made by the opening or closing of the circuit may be hermetically sealed to prevent the possibility of fire hazard; and in which such a mechanism provides the means for an explosion proof relay.

Other objects of the invention are to provide a switch mechanism bearing the above objects in mind which is of simple construction, has a minimum number of parts, is inexpensive to manufacture, and efiicient in operation.

For other objects and for a better understanding of the invention, reference may be had to the following detailed description taken in connection with the accompanying drawing, in which:

Fig. l is a perspective view shown partly in section of a preferred embodiment of the present invention and shown in a switch opened position;

Fig. 2 is a circuit diagram of the device showing the same in a switch closed position; and

Fig. 3 is a circuit diagram showing the device in a switch open position.

Referring now more in detail to the drawing, and more particularly to Fig. 1, indicates a hollow cylindrical housing of electrically non-conductive material, the upper end of which is closed by a circular top wall 11 of the same material, substantially as illustrated.

12 represents a pair of electrical terminals of elongated cylindrical shape integrally formed at their lower ends with the reduced cylindrical portions 13 forming the shoulders 14, the terminals 12 being formed of magnetic iron or ferrous material and preferably being silver plated to increase their electrical conductivity. The lower ends of the terminals 12, as shown in Fig. l, are suitably mounted in the top wall 11, with the extensions 13 extending therethrough, the shoulder 14 abutting the upper surface of the top wall 11. The lower ends of the extensions 13 are preferably provided with the silver contact surfaces 15. The upper ends of the terminals 12 are integrally formed with the reduced cylindrical extensions 16 adapted to be connected into the circuit of the device which is to be controlled by the switch mechanism forming the subject matter of the present invention.

The lower end of the casing 10 preferably is provided with an enlarged internally threaded bore 17 forming a shoulder 18 against which is positioned a diaphragm 19 of substantially circular shape and formed of non-magnetic material, the diaphragm 19 through its center being integrally formed with the raised ridge or barrier 20.

A lower hollow cylindrical casing 21 may be provided for vertical alignment with the upper casing 10 and secured thereto by means of the reduced externally threaded extension 22 integrally formed at its upper end and which is screwed into the internally threaded 'bore 17 to secure the diaphragm 19 in place, the casing 21, when used, being'similarly formed of electrically nonconductive material and having secured thereto a circular bottom wall 23 of the same material to complete the housing.

An operating shaft 24 is integrally formed at its upper end with the reduced smooth cylindrical extension 25 which is rotatably mounted in the center opening 26 provided in the bottom wall 23, the extension 25 extending upwardly and downwardly from the bottom wall to mount thereon the circular washers 27 and 28 to reduce friction. The upper end of the extension 25 is integrally formed with the reduced externally threaded extension 29 which is screw threaded into a substantially cylindrical permanent magnet 30, the periphery and top of the permanent magnet 30 being freely spaced from the casing 21 and diaphragm 19. The permanent magnet is provided with a transverse groove 31 extending downwardly from the upper surface thereof and is provided with the south pole 32 and the north pole 33.

A second cylindrical permanent magnet 34 is positioned within the casing 10 above diaphragm 19, being provided on its undersurface with a transverse groove 35 which slidably receives therewithin the barrier or ridge '20 whereby to prevent rotational movement of the permanent magnet 34 about a vertical axis, as'will be obvious. The permanent magnet 34 is provided with the north pole 36 and the south pole 37. The upper surface of the permanent magnet 34 may be provided with a silver coated layer 38 to increase the electrical conductivity of the same.

In operation, as the magnet 32 is rotated through 360 degrees by means of the operating shaft 24, the polarity of the same will alternately attract and repel the permanent magnet 34 which latter is fixed angularly. When the magnets are aligned as shown in Fig. 2, the like poles repel, forcing the magnet 34 and the silver coated surface thereof against the terminals 13 and silver contacts 15 thereof whereby to close the circuit. During this period of repulsion, the magnet 34 is attracted by the iron core of the terminals 12 to minimize the tendency to intermittent circuit interruption due to vibration and to the appreciable mass of the magnet 34. Upon further rotation of the magnet 32, to the position of Fig. 3 and Fig. 1, unlike poles attract and the force of the magnetic attraction between the magnets 32 and 34 greatly overcomes the attractive forces of the terminals 12 for the magnet 34 and the circuit is rapidly broken. This snap action is valuable from the electro-mechanical viewpoint and operates to extend the life of the contacts.

It will be noted that the size or shape of the magnets is largely immaterial, in view of a minimum requirement for flux. It will also be noted that the permanent magnet 34 is prevented from aligning itself with the magnet 32 by means of the groove 35 and barrier 20. Thus, the magnet 34 can only have vertical reciprocating motion within the casing.

If desired, the housing may be filled with a suitable medium such as nitrogen under pressure to provide excellent quenching of the electrical are between the terminals 12 and their contacts 15. A gas or liquid may be provided within the housing, as circumstances require. For example, transformer oil may be used. When such an incompressible fluid is provided within the housing, the switch may be operated under conditions of great external pressure, even though the diaphragm 19 is relatively thin (the pressure being equal on both sides).

While various changes may be made in the detail construction, it shall be understood that such changes shall be within the spirit and scope of the present invention as defined by the appended claims.

What I claim as new and desire to protect by Letters Patent of the United States is:

1. A switch mechanism of the character described, adapted for submerged use in the cavity of a fluid flowrneter, comprising an electrically non-conductive housing, a single reciprocable member consisting of a permanent magnet positioned Within said housing for high speed vibratory movement therein, said magnet having north and south ploes and a transverse groove therebetween at one end thereof and an electrically conductive surface at the opposite end thereof, a pair of terminals fixedly mounted within one end of said housing and extending into the interior thereof, closely adjacent and adapted directly to be contacted by the electrically conductive surface of said magnet, an electrically non-conductive diaphragm, closing the end of said housing remote from said terminals, having a transverse ridge nested within said groove to prevent angular displacement of said magnet, and a second permanent axially rotatable magnet, having north and south poles, positioned on the opposite side of said diaphragm in spaced relation thereto and freely rotatable at high speed within said housing, alternately to repel 4 and attract said first permanent magnet and to open and close said terminals when said second permanent magnet is rotated, whereby each complete revolution of the rotary magnet is translated into an electric impulse through the medium of the vibratory action of the reciprocating magnet.

2. In a switch mechanism according to claim 1, said terminals being formed of magnetically permeable material and being coated with electrically conductive material, whereby to attract said first permanent magnet to augment the repulsion thereto of said second permanent magnet and to impart a snap action to the switch mechanism.

3. A switch mechanism according to claim 1, said housing being substantially cylindrical, said first and second permanent magnets being substantially cylindrical,

said first permanent magnet having said groove intersect- References Cited in the file of this patent UNITED STATES PATENTS 1,874,199 Lingo et a1 Aug. 30, 1932 2,039,230 Lamb Apr. 28, 1936 2,353,740 Malone July 18, 1944 2,464,886 OReilly Mar. 22, 1949 2,521,723 Hubbell Sept. 12, 1950 2,543,014 Grace Feb. 27, 1951 2,548,581 Bigelow Apr. 10, 1951 2,584,907 Nelson Feb. 5, 1952 

